Q. I’m newly pregnant and my libido has been very up and down. I’m aware that I won’t be able to have sex for a while after the birth. What will happen to my libido during my pregnancy and is there anything I can do, as I don’t want to lose the sexual closeness that I have with my husband.

A. Pregnancy. It can be the best of times and the worst of times. The body that you have so reliably inhabited for decades suddenly becomes an alien. Your hormones board a rollercoaster, taking your libido with them, and for the next nine months, they skyrocket, loop the loop and crash back down with no regard whatsoever for the impact that they are having on you, or your relationship. Self-confidence can take a huge hit too, as your body changes. Yet on the plus side, being pregnant is the most incredible experience.

Although no two pregnancies are identical, seven billion babies and counting means that we can now predict, with a reasonable degree of certainty, what will happen to you, and your libido, during the 40 weeks of pregnancy. During the first trimester, your levels of oestrogen and progesterone increase dramatically. These months can be blighted by tiredness, nausea, and painful breasts, and as a result the activity that got you pregnant in the first place is often out of the question. Other women find that increased blood flow to the pelvis and the genitals leaves them in an almost perpetual state of arousal. Women normally have about 100ml of blood per minute flowing through the uterine artery. In the first six weeks of pregnancy this increases to about 120ml per minute and by the end of the final trimester it increases to a whopping 350ml per minute.

After about 12 weeks, your hormone levels will begin to drop, and you should feel less sick and more energetic. The escalating levels of blood circulating around your pelvis may, at this point, lead to a decrease in sensitivity, so you may need more stimulation during sex. A feeling of “fullness” after orgasm is also common, which can be a bit uncomfortable — almost like a throbbing ache, which takes a little while to dissipate. In the third trimester, weight gain, back pain, difficulty sleeping and indigestion may, once again, decrease your sexual drive. In later pregnancy there are certain positions which are more comfortable — spooning, for example, which is particularly gentle because penetration is much more shallow and your bump can be supported with a pillow. In late pregnancy, orgasm can also begin to trigger abdominal cramps and mild contractions. This can be a little unsettling, but they generally pass within a few minutes.

The critical variable during pregnancy is not really your libido, but your relationship. If women find pregnancy challenging, men often find it terrifying, particularly once the baby begins to make itself visible. Although sex is safe during all three trimesters (unless a woman has a low-lying placenta, a history of miscarriage, or is prone to premature labour), men can sometimes be squeamish about sex during pregnancy. Reluctant to articulate these very common insecurities, men will often try to avoid sex altogether; a strategy that can be misinterpreted as rejection by their partners.

Still, Mother Nature knows what she is doing, and by the time you hit the 28-week mark, the milk-producing hormone prolactin will kick in and completely suppress your sex drive. Sex will be the last thing on your mind. Research done by the department of anthropology at Northwestern University confirms that levels of the male sex hormone testosterone decline during pregnancy and remain substantially reduced in men who take an active role in caring for their babies. After the birth, doctors advise women to resist the temptation to have sex for six weeks, particularly if they have had stitches, but in reality, most new parents spend the first six months hankering after something else beginning with S. Sleep.